Certain pharmaceuticals can be administered in powdered form through inhalation of the powdered pharmaceutical into the lungs. This type of pharmaceutical delivery has several advantages. It eliminates the requirement for the use of syringes and needles, which many patients are uncomfortable with. Also, certain pharmaceuticals have a relatively short shelf life when in liquid form. Therefore, administration in powdered form eliminates the necessity to reconstitute the pharmaceutical with a liquid carrier.
Although not all pharmaceutical products are suitable for it being administered in a powdered form, many pharmaceuticals have been formulated for inhalation into the lungs. For example, Novo Nordisk of Bagsvaerd, Denmark, sells a nasal insulin preparation which is inhaled by the user. Other types of pharmaceuticals are administered in powdered form as well. Another pharmaceutical for oral inhalation by asthmatic patients is sold by Glaxo of Bern, Switzerland. The medication is delivered by a device, sold as the DISKHALER.RTM., which has a rotatable disk with a number of regions containing the pharmaceutical. The disk is rotated to position one of the pharmaceutical-containing packets in line with a needle; the needle punctures the packet to allow the pharmaceutical to be inhaled. Another type of powdered pharmaceutical delivery device is sold by Fisons Corporation of Bedford, Mass., under the trademark SpinHaler.RTM.. It uses a gel capsule containing the powdered pharmaceutical. The capsule is pierced by a needle which allows the pharmaceutical to be inhaled through the mouth.
One of the problems with prior art powdered pharmaceutical delivery devices when the device is reused, as is normal. The powdered pharmaceutical often clings to, coats or even cakes onto surfaces of the device. The surfaces, which often have been moistened by the user's breath, can become contaminated; the contaminated surfaces can create health problems during subsequent use due to the bacterial contamination.